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This research is inspired by the challenge of providing situational awareness to a ship looking for leads in the ice to navigate the Canadian Arctic. To address this challenge, this paper proposes piecewise-deterministic quasi-static simultaneous localization and mapping (PDQS-SLAM). PDQS-SLAM relaxes the static assumption that is inherent to traditional SLAM algorithms by incorporating landmark kinematic motion models in the graph construction. It then generalizes to more complex dynamic environments by detecting inevitable disruptions to the landmark’s motion model. This is achieved by augmenting the definition of a loop closure factor to include a state, governed by a finite state machine, that captures the edge’s behaviour over time. Simulations and laboratory experiments demonstrate that the localization and mapping errors of PDQS-SLAM in a dynamic environment with mobile landmarks that experience changes in their motion model were similar to the baseline static SLAM in a static environment. This represents a capability that is needed for persistent autonomous operations in complex environments populated with slowly-evolving landmarks, such as the Canadian marine Arctic. [ABSTRACT FROM AUTHOR]

The objective of this paper is to develop a novel consensus algorithm or protocol for multi-agent systems in the event of communication link failure over the network. The structure or topology of the system is modeled by an algebraic graph theory, and considered as a discrete time-invariant system with a second-order dynamics. Bernoulli distribution is applied to represent the data dropout during operation. The sufficient conditions for the stabilization controller design is developed by Lyapunov-based methodologies and Linear matrix inequality (LMIs) techniques. The feasibility of the given LMIs is analyzed to verify the stabilization of controller design, which ensures the MAS to achieve the consensus. Leader-following numerical simulations with a group of agents are successfully conducted based on the effect of data losses, initial values, communication weights, and number of agents to demonstrate the effectiveness of the novel consensus algorithm in this paper. Finally, experimental studies are carried out by using two Pioneer 3-DX mobile robots and one Pioneer 3-AT mobile robot as a team to verify the proposed work. [ABSTRACT FROM AUTHOR]

The stability and stabilisation problems for a series of continuous stochastic singular systems with multiple time-varying delays are studied in this paper. First, a useful lemma is proposed and a delay-distribution-dependent Lyapunov functional is constructed. Then, a novel delay-distribution-dependent condition is given to ensure the unforced stochastic singular systems to be regular and impulse-free. The mean-square exponential stability of the whole system is guaranteed under the proposed lemma. As a result, a suitable feedback controller is designed via strict linear matrix inequality such that the system's stabilisation problem is guaranteed. Finally, numerical examples are illustrated to show the proposed result are less conservative than the existing ones and the potential of such technology. [ABSTRACT FROM AUTHOR]

The stochastic reliable control problem for networked control systems (NCSs) subject to actuator failure and input saturation is investigated in this paper. In order to get the relationship between the maximum allowable consecutive packet dropouts, the packet dropout probability, the actuator failure matrix and the input saturation, a packet dropout probability dependent condition is given via linear matrix inequality (LMI) technology. Then, a suitable reliable controller is designed to ensure the closed-loop system to be exponentially mean square stable against actuator failures and input saturation. Finally, numerical examples are provided to show the effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]